Os novos cabos padrão USB-C são reversíveis, flippable e os circuitos do dispositivo comunicam entre si para regular a quantidade de energia transferida. Eu esperaria ver algum tipo de painel de configurações que permite selecionar de que forma a energia é transferida.
De um artigo da Yahoo Tech que tem mais detalhes e animações ...
Type-C also offers something called bidirectional charging. Have you ever had 100 percent battery life on your tablet and 0 percent on your phone, and wished you could just transfer battery power from the tablet to the phone? With Type C, you’ll be able to do just that. You’ll not only be able to charge your laptop, smartphone, or tablet from the wall, you’ll be able to charge it from other devices, too. So you could use one laptop to charge another, or a phone to charge a tablet, or an MP3 player to charge a toaster (if it can get charged via Type-C).
É novo em folha, por isso apenas alguns dispositivos importantes o têm ...
Right now the only devices using Type-C are Google’s new Chromebook Pixel, Apple’s recently announced MacBook, Nokia’s N1 tablet, and a few storage devices.